Everyone and their brother makes an AR-15 these days. It is without a doubt the most popular design in the United States, and for good reason — it’s like Legos for grown ups. More and more “traditional” gun companies are throwing their hats in the ring, producing budget priced AR-15 copies for the civilian market. And the latest of those is Mossberg with their “Mossberg Modern Rifle.” But is there anything new and different that they bring to the table?

Mossberg’s MMR line came out in June of last year, with the “flagship” being a varmint hunter version sporting a long barrel and camo pattern. But they also announced a “tactical” version of the rifle with the standard “evil black rifle” black finish and priced it to compete in the budget AR-15 market. With competitors like the Smith & Wesson M&P-15 Sport and the Bushmaster A1 already firmly entrenched in the market they had some catching up to do.

The overall design is a bone stock AR-15. The major components are all Mossberg — the lower is stamped with Mossy’s Swede-inspired logo and the barrel bears the typical Mossy markings. And while everything looks right at first glance, there are some minor fit and finish issues with the gun. For example, despite the upper and lower supposedly made in the same place, they don’t quite match up. A minor gripe I know, but like a small crack under the wing of an airplane it’s a somewhat disconcerting indicator of possible problems below the surface.

The gun comes with most of the standard “mil spec” gubbins, which means the trigger is absolutely miserable. The stock trigger in most parts kits is a jagged, craggy affair with enough slack to make you think you’ve picked up a Sig P226 instead. And it has a typical mil spec break that would make the Geissele family sob uncontrollably. The MMR’s trigger feels like an unholy combination of a single stage trigger and a two stage trigger, with none of the benefits of either.

There’s also no forward assist, much like the S&W M&P-15 Sport design. But since in the hundreds of thousands of rounds I’ve put downrange with AR-15 rifles I’ve never once had the need to use my forward assist, I don’t really mind. And if push comes to shove, the scallop on the bolt carrier works just as well as a forward assist. Despite the lack of a FA the bolt still has the ratchet cutouts on the side to allow its use, though.

The grip, which is one of the only things that doesn’t appear to be made by Mossberg, is also rather unusual. It lowers your hand in relation to the gun (compared to a standard A2 grip), and while that does make the trigger guard a little larger and gives you a more comfortable grip, it also makes flipping the safety on or off quite difficult – except for those with large hands.

The Mossberg does have a significant leg up on the competition, however.

The S&W and the Spike’s AR-15s are cheaper, BUT neither has a free-floating barrel. The vast majority of “budget” AR-15 rifles use the standard M4 handguards that attach directly to a bracket on the gas block of the barrel and the delta ring next to the receiver. Since the handguards are directly attached to the barrel any force applied to the handguards has a tendency to bend the barrel (however slightly), throwing your rounds off target.

The MMR however doesn’t have this problem, thanks to its free-floating handguards and low profile gas block. This provides a tangible increase in accuracy over the competition.

The Mossberg not only has a free floating barrel and handguards, it has m1913 rails on all four sides of those handguards. That means you can hang all your favorite toys on this rifle with no problem, including lights, lasers, and grenade launchers. Unless you already used that government profile barrel to attach an underslung M203, that is.

But while the handguards are certainly, well, handy, they also have incredibly sharp edges. That, combined with the fact that they stick out a whole extra centimeter on each side than is really necessary means they are mighty uncomfortable. If I had just purchased this gun, a set of handguard covers would be first on my list of things to dress it up.

So, are the annoyances worth the added accuracy? Well…

In a word, “yes.” In two words, “hell yes.” That right there would have been a 1 MoA 3-round group at 50 yards, but thanks to the 5 round policy it expanded slightly to a 2 MoA group. Still, for a budget priced AR-15 that’s a thing of beauty. That was shot with the help of a spare scope I had laying around, and I have every confidence that if you improve the trigger and add a bipod or some other stabilization equipment (instead of shooting off a sandbag) you can keep that group to 1 MoA or less. (Extra special thanks to Bracken Range in San Antonio for the range time!)

This rifle has many great features…on paper. The free-floating barrel is a great touch and the optional iron sights are quite nice. But in reality, the rifle is almost as uncomfortable to shoot as this cactus – in its new-from-the-factory condition, at least. Some nice rail covers, a change of triggers and a different grip and I think this would make a fine rifle for everything from 3-gun competitions to hunting.

Despite the drawbacks, this might just be one of the best budget AR-15 rifles you can buy. Considering the competition, this rifle is available for less coin than most of the other offerings and gives the end user far more options in terms of how they want to kit their rifles. Oh, and it also allows them to be more accurate thanks to the free floating barrel.

Ratings (Out of Five Stars):
All ratings are relative to other similar guns, and the final score IS NOT calculated from the constituent scores.

Accuracy: * * * * *
The free floating barrel is a very nice touch. Combined with the heavy government profile barrel I’ve found it to be an extremely accurate gun, and I have no doubt that some minor upgrades would improve it further.

Ergonomics (Handling): * *
Oh dear God the handguards…

Ergonomics (Firing): * *
The trigger absolutely kills this rating.

Reliability: * * * * *
As long as you keep it nice and lubed (we’re pretty sure the test model came out of a vat of motor oil) everything will be fine.

Customization: * * * * *
The full length m1913 rail on the top and the rails on the side of the handguards make it very easy to customize this rifle.

Overall Rating: * * * *Compared to everything else out there, and even including my complaints about the trigger and the handguards, its not a bad rifle. Compared to the other sub-$1k AR-15s, its fantastic. You’re $100 in upgrades away from a rifle I would be comfortable using in 3-gun competitions.

Full Disclosure: This rifle was provided by Mossberg for the purposes of reviewing for the site. It is en route back to Mossberg.

About Nick Leghorn

Nick Leghorn is a gun nerd living and working in San Antonio, Texas. In his free time, he's a competition shooter (USPSA, 3-gun and NRA High Power), private pilot, and enjoys mixing statistics and science with firearms. Now on sale: Getting Started with Firearms by yours truly!

67 Responses to Gun Review: Mossberg MMR Tactical (AR-15)

A four-star AR for $700? I think any AR guy is capable of replacing the trigger and handgrip and adding some rail guards themselves. It’s much easier and cheaper than adding a free-floated handguard to a stock M4gery, at any rate.

And here I thought Mossberg had expanded into pharmaceuticals and was producing a new Measels, Mumps, and Rubella vaccine.

This looks rather nice, especially since I’m looking for my first AR and M&P Sports are currently a legend only heard about on the Intarwebs. Sounds like with some Magpul gear, this could be awesome.

For a general AR (mostly plinking, hopefully some competition in the future, but not high end), what trigger replacements would you suggest? Timminy and Geiselle (spelling is boned, I know) that have been reviewed on here seem to be pretty top of the line.

If you can find and afford a Colt M4 NIB with one of the following stampings buy it asap:

Second Best: Says “Colts Law Enforcement Carbine Cal 5.56MM” on the left side … also has the right side stamping that says “Restricted Military/Government Law Enforcement/Export Use Only” (These were made during the assault rifle ban)

Best: Say “Colts Law Enforcement Carbine Cal 5.56MM” on the left side … right side is blank. (Kinda rarer as they were changing out stamps right when the assault rifle ban was repealed)

All the newest ones just say “M4 Carbine Cal 5.56MM” on the right side.

All of these are now legal for purchase. I suggest also making sure it says “Colt Defense” in front of the safety on the left side instead of the standard Colt manufacturing marking. The first is the mil-spec line .. the second is the civilian build line.

Good Luck in your collecting. It does look like a nice affordable M4 btw if you don’t have the big bucks to spend for just the Colt name. It also has the free floating barrel like the 6940.

“All the newest ones just say “M4 Carbine Cal 5.56MM” on the right side.”
My bad LEFT side .. I wish I could edit posts. Too many customers .. too little time to proofread every little thing …

Also remember to think about the twist ratio when getting yourself a AR-15/M4 style rifle. (Yes there are also some 1:8 before someone says it). A 1:7 is better if you want to run higher grain rounds through it.

Nice report
I’d be interested in trying the Stark Industries kung fu Pistol Grip just to see if it offered an improved trigger press.
The rails:
I’m not a fan of fat handguards that cut like a Cuisenart, I have to buy my own clothes and bandages which makes me picky, but that’s just me.
No Foward Assist:
There was an extremely good reason the US military withdrew all non-FA M-16s and replaced them w/FA A1 models; soldiers were royaly peeved that thier rifles were turning into coat racks in combat, this is very bad JuJu.
Concider that the owner of an econ. grade AR will be shooting tons of cheap steel cased ammo, if a loaded round jams part way into the chamber, that can be very bad indeed.
We are talking a specific market/price point AR, the floating barrel is a nice touch but a Chip McCormic trigger will give the same improvement to standard ARs, improve trigger reset and has those sexy looking pins. It sounds like the Mossy trigger needs to be junked which bumps the actual street cost up to $870. I am troubeled by the fit and finish of the Mossy, the S&W AR seems to be superior here.
Perhaps this is the next Vundergewehr but I have reservations.
Here is a trick to instantly reduce your group size:
Stop aiming at 2MOA targets and instead aim at a .5MOA target, especialy at 50 yards,,,with a scope.

Correct me if I’m wrong, I’ve never built or owned an AR before (hope to rectify that soon). Can’t you just buy a stripped upper with a FA and put it on? Nick said the bolt was made to use one, just not the upper. Could be wrong.

I wouldn’t ever shoot a round of steel through any AR I ever shot. I keep it for home defense, preloaded in mags, should I ever need it, which I hope that I don’t. If you check Gunbot, decent 5.56 (and .223) can be had, even nowadays, for 60 cents a round. Cabelas has had deals lately for 100rd of brass for $58.90 shipped. Brass/copper good. Steel bad.

Rifles like this are nice for a budget price. Don’t fall for a magpul, socomm , etc AR-15 style pre-accessorized. Everyone likes something different. If you are gonna spend the $$$ put on what you want instead of the “standard custom Joe” model. Buy a base model and deck it out to your own preferences.

Guns should only have as much rail as they need, and only where they need it. Unnecessary rail might look cool, but it tears up your hands and chews up any other gear it rubs against. The worst cheese-grater ever was a picatinny fore-end on a pump shotgun. Crimson Trace had one of these as a loaner for their (otherwise excellent) 3-gun training course for noobs, and my left hand was scabbed and sore for days afterwards.

I expect that anyone subject to the least amount of AR-related peer-pressure will replace that grip in a heartbeat. It appears to be one of the products referred to as a “grip of shame” used by those who botch the AR assembly by bending or breaking the trigger guard tabs on their lower.

It would be interesting to put a Slidefire bump stock on one of these and see how well they hold up to simulated full-Auto. We sell many of those to people with AR-15 and AK-47’s although I try to get them to do the paperwork and wait for a real full-auto. They do help sell a lot more range ammo

A free-floating barrel is one in which the barrel and stock are designed to not touch at any point along the barrel’s length. The barrel is attached to its receiver , which is attached to the stock, but the barrel “floats freely” without any contact with other gun parts, other than the rifle’s sights. This minimizes the variance in possible mechanical pressure distortions of the barrel alignment, and allows vibration to occur at the natural frequency .

Nick, just purchased my first real AR 15, I have a Colt AR 15/22 already. It’s a Sig RM400-16B SRP with scope for $964.00 out the door. With one mag and a two point sling included. I own two Sig handguns and know that Sig has a good reputation, and do realize this is probably an entry level AR.

It is chambered in 556×45 which from what I’ve read on here is better to get an AR chambered in 556/223 than 223/556, unless I read that wrong.

What brand/s mags do you recommend, considering I only got one, and if I decide to change triggers, which do you prefer?

I fell in love (not in the physical sense) with the M16 forty some years ago, and it’s only taken me that long to finally purchase one. Hope I didn’t make a mistake with this particular one!

Can you recommend a good aftermarket trigger replacement/upgrade in the 200-300 dollar range (something that would keep the cost on this weapon under a grand street price) and remove what seems to be the biggest issue with this weapon?

Great review – I thought of it when I went to my gun shop last night to purchase an AR. When they offered this among their measly pickin’s I recalled that you’d given it a thumbs up as a good option for someone new to the AR world and bought it. I paid close to MSRP, so some price inflation but not a total gouging.

Where I live you are limited to 20 round mags (soon to go down to 10). Mossberg’s notes on this are a bit cryptic about magazine compatibility. They say something like it will take most AR type magazines.

Any, actually. Thermold 20rd mags (they’re inexpensive as hell) are fine, but you may need to give them a whack underneath so they seat properly (it’s the mag, not the rifle) – you can find them for as little as 6 bucks nowadays. So you bought the MMR? HOW AWESOME IS THIS RIFLE!!!!!

But yeah, any 5.56/.223 AR-15/M4 mags will work on the rifle.

I am the envy of all my AR-owning friends now. One of my best friends bought one yesterday. Smart move on his part.

By the way, if you’re looking for cheap (and amazing) optics, search Amazon for either 3-9×40 or 6-24×50 and sort by price. The two sold by “cvlife” are tremendous. I have the 3-9×40 and it’s AMAZING. $50 and they rival name brand scopes that cost $1000 or more (yes, really)

The scope is so accurate, and holds zero like a champ, when coupled with the MMR. Such a sick setup. I could not possibly be happier with my purchase. It’s worth twice the money that it cost me ($749 new)

Absolutely perfect rifle, IMO. I don’t care about a forward assist (a modern precision-built rifle shouldn’t need one), and I don’t take issue with the trigger or grip, as the reviewer did.

The Mossberg MMR is the best rifle on the market for under $1500 retail. Hands down.

Everyone who’s fired my rifle wants to steal it. It’s a bit “kicky” – recoil – and I love that. The accuracy is unreal. I would buy another one if I had a need for another AR-15 (I can’t convince myself yet that I do indeed need another one)

The removable BUIS on this rifle rule, too. I think they’re better than the Magpuls.

I already bought a Mossberg MMR AR 15 earlier this year I was just checking out to see if there were any bad reviews on the rifle. Im glad to see there are not many bad things to say other than a couple of things that I can change myself. On my rifle I put the iron sights with the handle and a tactical vertical grip which has a laser sight, strobe light, and flashlight on the grip itself, there are two buttons on the grip one for the laser sight and the other for the flashlight/strobelight. But when I was trying to zero the laser sight grip with a laser bore sighter I could not get the two dots to line up properly, any info on what I can do to get the laser sight dialed in.

I just bought an Intacto Arms AR15 and it shoots sub MOA consistently. I think there are a few smaller manufacturers that can turn out a better quality/accuracy rifle for the money than the big mfgs. 1500 is way too much for what you are getting on this MMR, just paying for the name.

I like having something different, but that is just my taste. Plus I’m a big fan of billet parts and I don’t like quad rails at all.

Thank you for a thorough unbiased review………….after reading the mostly really positive attributes of this gun, i chose to buy one……..i added a cheap 2.5-10 power scope, a bipod adapter on the bottom pic rail, and i removed the open sights…….i like the style and comfort of the Stark pistol grip. somewhere down the road, i will add a CMC drop in trigger, and ive got a 24″ Bull Barrel Stag Arms upper on order. This gun shoots nicely, a whole lotta gun for a little over $700

I have one. During the buying decision, in left hand a Colt at $1900, in my right hand a Mossberg MMR for $900. I have added plastic covers for the rail and trigger work was just completed. The re-worked trigger made a lot of difference and I would suggest this is an upgrade worth the money.

A thousand rounds and I have zero complaints. It’s really a lot of fun and the wife also enjoy shooting the AR, but not as much as her tactical Mossberg 20 gauge.

Hey Nick, another question. How do the Mossberg sights compare to other detachable sights on the market? Would I be better off buying the MMR without sights and buying something like the Magpul MBUS that fold down (and add $50 to $60 to the overall cost of the rifle?) I like the idea of keeping the sights folded while not in use. I don’t have any hands-on experience with the MBUS’s or the Mossberg sights – maybe it’s not a big deal.
Thanks

Came across this article while looking to repair a problem with an MMR. Buddy bought one that has been more time at Mossberg than he has owned it. At first it seemed to shoot fine. After a few range sessions started jamming up like crazy. First trip to Mossberg gun came back after about 2 months with some lube on it and no note as to what the problem was… Range trip, started jamming up after the first magazine… Happens with steel and polymer mags so it’s not the mags… Sent back to Mossberg and about 2 months later came back with grease on it. No note as to what was fixed, etc… So I told him I would take it and fix it for him… I have taken it apart and noticed that the upper receiver’s feed ramps are just small dots and not very deep at all. It is my theory that this is what’s causing the problem. They actually look like there is metal kind of sticking out a bit. Compared to my budget Aero Precision upper, the Mossy looks like crap. Buddy gave me the go ahead to replace the upper and barrel and get this thing going. Total spent will be around $300 so a total of about $950 spent on this junk to get it to work. Buddy got so fed up he went and got a Ruger SR-556… Yes, it’s $1200 but it works and has not jammed once… I’m going to try to cut the feed ramps a bit deeper on the Mossy upper and see if I can build a budget beater gun with it.

Without specific details as to the “jamming” it’s hard to diagnose the cause. Are rounds hanging up part-way into the chamber? Not extracting from the chamber after firing? Extracting from the chamber but not being ejected from the upper receiver?

Could be the barrel, could be the gas system, could be the upper receiver…

Could be the magazine. Have you used “known to be good in other rifles” magazines to test? US GI or quality commercial ones from Magpul, etc?

And it could be the ammunition. Are you using US GI-spec ammo like Federal XM193, or just whatever was cheapest on the shelf the day you were at the gun shop?

If the feed ramps aren’t cut properly that could certainly cause intermittent feeding problems. Especially if the rifle is being run without enough lube, and/or less-than-perfect ammunition is being used.

Cutting the feed ramps a bit deeper might help. But remember that it’s always easier to remove metal than to put it back. Proper “M4 feed ramps” shouldn’t extend too far into the aluminum of the upper receiver. What is important is that there is no lip or step between the ramp in the upper and the ramp in the steel barrel extension. Any lip or step there can catch the cartridge and slow down its chambering enough to result in a jam.

Here’s an image from ar15.com that illustrates what feed ramps should and should not look like:

The Mossberg barrels appear to be decent quality, so it might be worth keeping the barrel and merely replacing the upper receiver.

Check Palmetto State Armory for some options. You can get a “blemished” upper from them very cheaply — I’ve bought several for projects and the worst “blemish” I’ve found to date was some uneven dying of the anodizing on the interior of the upper receiver. A stripped “blemish” upper is usually $50 but they go on sale for $40 frequently. The dust cover will swap right over to a replacement upper, but you’ll need to add a forward assist. FA parts are about $12 from multiple sources.

Removing and installing an AR barrel requires a barrel-nut wrench and a barrel vise, or a vise and a set of receiver blocks to hold the receiver. With the cheesegrater handguard on the MMR, it may also require a proprietary wrench to remove?

If you want to reuse the Mossberg cheesgrater at that point, installation should be the reverse of removal. If you prefer normal handguards, and/or a front sight mounted to the barrel, then you’ll probably need to remove the gas block in order to fit a handguard “delta” ring and/or replacement gas block or front sight base. I don’t know what sort of gas block Mossberg is using on the MMR, and if it’s pinned, held in place by set-screws or clamped to the barrel. The method of mounting will dictate the means necessary to remove the gas block, and may limit your options for replacement.